EC2254 LINEAR INTEGRATED CIRCUITS ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

EC 2254 LINEAR INTEGRATED CIRCUITS ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, EC2254 LINEAR INTEGRATED CIRCUITS IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

B.E./B.Tech. DEGREE EXAMINATION, APRIL/MAY 2010

Fourth Semester

Electronics and Communication Engineering

EC2254 — LINEAR INTEGRATED CIRCUITS

(Regulation 2008)

Time: Three hours Maximum: 100 Marks

Answer ALL Questions

PART A — (10 × 2 = 20 Marks)

1. What is an integrated circuit?
2. What is current mirror?
3. Give the schematic of op-amp based current to voltage converter.
4. Draw the circuit diagram of differentiator and give its output equation.
5. What is a VCO?
6. Draw the relation between the capture ranges and lock range in a PLL.
7. Define resolution of a data converter.
8. Give the advantages of integrating type ADC.
9. Draw the internal circuit for audio power amplifier.
10. What are the three different wave forms generated by ICL8038?

PART B — (5 × 16 = 80 Marks)

11. (a) (i) Define CMRR. Draw the circuit of an Op-amp differential amplifier
and give the expression for CMRR. (8)
(ii) Define Slew Rate. Explain the cause of slew rate and derive an
expression for Slew rate for an op-amp voltage follower. (8)
Or
(b) Briefly explain the various processes involved in fabricating monolithic
IC which integrates bipolar transistor, diode, capacitor and resistor. (16)
12. (a) (i) Design a first order Low-pass filter for cut-off frequency of 2 KHz
and pass-band gain of 2. (8)
(ii) Explain a positive clipper circuit using an Op-amp and a diode with
neat diagrams. (8)
Or
(b) (i) Design a circuit to implement 2 1 4 3 0 2 25 . 1 273 . 0 545 . 0 V V V V V − − + = .
(8)
(ii) Draw and explain a simple Op-amp differentiator. Mention its
limitations. Explain with a neat diagram how it can be overcome in
a practical differentiator. Design an Op-amp differentiator that will
differentiate an input signal with maximum frequency
Hz 100 fmax = . (8)
13. (a) (i) With a neat diagram explain the variable transconductance
technique in analog multiplier and give its output equation. (8)
(ii) Briefly explain the working of voltage controlled oscillator. (8)
Or
(b) What are important building block of phase locked loop ( PLL) explain its
Working? (16)
14. (a) (i) Explain the working of R-2R ladder DAC. (8)
(ii) Explain the working of success approximation ADC. (8)
Or
(b) (i) A dual slope ABC uses a 16-bit counter and a 4 MHz clock rate. The
maximum input voltage is +10V. The maximum integrator output
voltage should be -8V when the counter has recycled through
n 2 counts. The capacitor used in the integrator is F µ 1 . 0 . Find the
value of resistor R of the integrator. (8)
(ii) What is a sample and hold circuit? Briefly explain its construction
and application. (8)
15. (a) (i) How is voltage regulators classified? Explain a series voltage
regulator. (8)
(ii) What is an optocoupler? Briefly explain its characteristics. (8)
Or
(b) With a neat circuit diagram and internal functional diagram explain the
working of 555 timers in astable mode. (16)

EC2252 Communication Theory nov/dec 2010 ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

Communication Theory nov/dec 2010 ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER EC2252 Communication Theory nov/dec 2010 , IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

B.E./B.Tech.Degree Examinations, November/December 2010

Regulations 2008

Fourth Semester

Electronics and Communication Engineering (ECE)

EC2252 Communication Theory

( Common to PTEC 2252 Communication Theory for B.E.(Part -Time)

Third Semester ECE - Regulations 2009)

Time: Three Hours Maximum: 100 Marks

Answer ALL Questions

Part A - (10 x 2 = 20 Marks)

1. How many AM broadcast stations can be accommodated in a 100 kHz bandwidth
if the highest frequency modulating a carrier i s 5 kHz?
2. State the applications of FDM.
3. Illustrate the relationship between FM and PM, with block diagrams.
4. Compare the transmission bandwidth required for Narrowband FM and Wide band
FM.
5. De¯ne a random variable. Specify the sample space and the random variable for a
coin tossing experiment.
6. What i s white noise? Give its characteristics.
7. De¯ne threshold e®ect in AM receiver.
8. De¯ne pre-emphasis and de-emphasis.
9. A source generates 3 messages with probability 0.5, 0.25, 0.25. Calculate source
entropy.
10. De¯ne Rate Bandwidth and Bandwidth effciency.

Part B - (5 x 16 = 80 Marks)

11. (a) (i) With the help of a neat diagram, explain the generation of DSB-SC using

Balanced modulator. (8)
(ii) Write about the coherent detection method in detail for DSB-SC and SSB-
SC. What happens when there i s phase mismatch? (8)
OR
11. (b) (i) Explain the concept of Frequency Translation. (4)
(ii) With aid of block diagram explain the principle of FDM. (8)
(iii) Illustrate the formation of Basic group and super group. (4)
12. (a) (i) De¯ne frequency modulation. Draw the FM waveform. Derive an expres-
sion for single tone frequency modulation.
(2 + 2 + 6)
(ii) Compare Narrowband and Wideband FM. (6)
OR
12. (b) (i) A 20 MHz i s frequency modulated by a sinusoidal signal such that the max-
imum frequency deviation i s 100 kHz. Determine the modulation index
and approximate bandwidth of the FM signal for the following modulating
signal frequencies,
(1) 1 kHz (2) 100 kHz and (3) 500 kHz. (8)
(ii) Derive the time domain expressions of FM and PM signals.
(8)
13. (a) (i) List the di®erent types of random process and give the de¯nitions. (10)
(ii) Write short notes on shot noise. (6)
OR
13. (b) (i) A mixer stage has a noise ¯gure of 20 dB and this i s preceded by an
ampli¯er that has a noise ¯gure of 9 dB and an available power gain of 15
dB. Calculate the overall noise ¯gure referred to the input. (8)
(ii) A receiver has a noise ¯gure of 12 dB and it is fed by a low noise ampli¯er
that has a gain of 50 dB and a noise temperature of 90 K. Calculate the
noise temperature of the receiver and the overall noise temperature of the
receiving system. Take room temperature as 290 K. (8)
14. (a) Derive the expression for ¯gure of merit of a AM receiver using envelope de-
tection. What do you infer from the expression? (16)
OR
14. (b) De¯ne and explain FM Threshold e®ect. With suitable diagram, explain
threshold reduction by FMFB demodulator. (16)
15. (a) (i) An Analog signal i s band limited to `B' Hz and sampled at Nyquist rate.
The sampled signals are quantized into 4 levels. Each level represents
one message. The probability of occurrence of the four messages are
p1=p3=1/8; p2=p4=3/8. Find out information rate of the source. (6)
(ii) Five source messages are probable to appear as m1 = 0:4, m2 = 0:15,
m3 = 0:15, m4 = 0:15, m5 = 0:15. Find coding e±ciency for (1) Shanon-
Fano coding, (2) Hu®man coding.
(10)
OR
15. (b) (i) Derive the channel capacity for Binary Symmetric channel.
(6)
(ii) Derive the channel capacity for band limited, power limited Gaussian
Channel. (10)

EC2252 Communication Theory ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

 Communication Theory ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT


ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, EC2252 Communication Theory IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

B.E./B.Tech.Degree Examinations,Apr/May 2010

Regulations 2008

Fourth Semester

Electronics and Communication Engineering

EC2252 Communication Theory

Time: Three Hours Maximum: 100 Marks

Answer ALL Questions

Part A - (10 x 2 = 20 Marks)

1. How many AM broadcast stations can be accommodated in a 100 kHz bandwidth
if the highest frequency modulating a carrier i s 5 kHz?
2. What are the causes of linear distortion?
3. Draw the block diagram of a method for generating a narrowband FM signal.
4. A carrier wave of frequency 100 MHz i s frequency modulated by a signal
20 sin(200¼ £ 103t):
What is bandwidth of FM signal if the frequency sensitivity of the modulation i s
25kHz=V .
5. When i s a random process called deterministic?
6. A receiver connected to an antenna of resistance of 50­ has an equivalent noise
resistance of 30­. Find the receiver noise ¯gure.
7. What are the characteristics of superheterodyne receivers?
8. What are the methods to improve FM threshold reduction?
9. De¯ne entropy function.
10. De¯ne Rate Bandwidth and Bandwidth e±ciency.

Part B - (5 x 16 = 80 Marks)

11. (a) (i) Draw an envelope detector circuit used for demodulation of AM and ex-
plain its operation. (10)
(ii) How SSB can be generated using Weaver's method? Illustrate with a neat
block diagram. (6)
OR
11. (b) (i) Discuss in detail about frequency translation and frequency division mul-
tiplexing technique with diagrams. (10)
(ii) Compare Amplitude Modulation and Frequency Modulation.
(6)
12. (a) (i) Using suitable Mathematical analysis show that FM modulation produces
in¯nite sideband. Also deduce an expression for the frequency modulated
output and its frequency spectrum. (10)
(ii) How can you generate an FM from PM and PM from FM?
(6)
OR
12. (b) (i) A 20 MHz i s frequency modulated by a sinusoidal signal such that the
maximum frequency deviation is 100 kHz. Determine the modulation index
and approximate bandwidth of the FM signal for the following modulating
signal frequencies,
(1) 1 kHz (2) 100 kHz and (3) 500 kHz. (8)
(ii) Derive the time domain expressions of FM and PM signals.
(8)
13. (a) (i) Give a random process, X(t) = Acos(!t+µ), where A and ! are constants
and µ is a uniform random variable. Show that X(t) is ergodic in both
mean and autocorrelation. (8)
(ii) Write a short note on shot noise and also explain about power spectral
density of shot noise. (8)
OR
13. (b) Write the details about narrow band noise and the properties of quadrature
components of narrowband noise. (16)
14. (a) Derive an expression for SNR at input (SNRc) and output of (SNRo) of a
coherent detector. (16)
OR
14. (b) (i) Explain pre-emphasis and De-emphasis in detail. (10)
(ii) Compare the performances of AM and FM systems. (6)
15. (a) (i) Find the code words for ¯ve symbols of the alphabet of a discrete memory-
less source with probability f0.4, 0.2, 0.2, 0.1, 0.1g, using Hu®man coding
and determine the source entropy and average code word length. (10)
(ii) Discuss the source coding theorem. (6)
OR
15. (b) (i) Derive the channel capacity of a continuous band limited white Gaussian
noise channel. (10)
(ii) Discuss about rate distortion theory. (6)

EC2251 ELECTRONIC CIRCUITS – II ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

 ELECTRONIC CIRCUITS – II ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

SuB CODE : EC2251

ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER,  EC2251 ELECTRONIC CIRCUITS – II IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

B.E./B.Tech. DEGREE EXAMINATION, APRIL/MAY 2010

Fourth Semester

Electronics and Communication Engineering

EC2251 — ELECTRONIC CIRCUITS – II

(Regulation 2008)

Time: Three hours Maximum: 100 Marks

Answer ALL Questions

PART A — (10 × 2 = 20 Marks)

1. What is the impact of negative feedback on noise in circuits?
2. Define sensitivity and desensitivity of gain in feedback amplifiers.
3. Mention two essential conditions for a circuit to maintain oscillations.
4. In a RC phase shift oscillator, if = = = K R R R 200 3 2 1 and
pF C C C 100 3 2 1 = = = , find the frequency of the oscillator.
5. Define tuned amplifier.
6. Define the term unloaded Q factor.
7. Give two applications of bistable multivibrator.
8. A 20 KHz, 75% duty cycle square wave is used to trigger continuously, a
monostable multivibrator with a triggered pulse duration of s µ 5 . What will be
the duty cycle of the waveform at the output of the monostable multivibrator?
9. Mention any two applications of blocking oscillator.
10. What is the function of time base circuit?

PART B — (5 × 16 = 80 Marks)

11. (a) (i) Explain how negative feedback acts on bandwidth, distortion, Input
Impedance and Output Impedance of a circuit. (8)
(ii) An amplifier has a mid-frequency gain of 100 and a bandwidth
of 200 KHz.
(1) What will be the new bandwidth and gain, if 5% negative
feedback is introduced?
(2) What should be the amount of feedback, if the bandwidth is to
be restricted to 1 MHz? (8)
Or
(b) (i) Explain voltage series and voltage shunt feedback connections. (8)
(ii) Explain Nyquist criterion to analyse the stability of feedback
amplifiers. (8)
12. (a) (i) Explain Armstrong oscillator and derive its frequency of oscillation.
(8)
(ii) A Colpitts oscillator is designed with pF C 100 1 = and
pF C 7500 2 = . The inductance is variable. Determine the range of
inductance values, if the frequency of oscillation is to vary between
950 KHz and 2050 KHz. (8)
Or
(b) (i) Explain Wien bridge oscillator and derive its frequency of
oscillation. (10)
(ii) Write a note on frequency stability of oscillators. (6)
13. (a) (i) Discuss about double tuned voltage amplifier. (8)
(ii) Discuss the effect of bandwidth on cascading single tuned
amplifiers. (8)
Or
(b) (i) Explain class ‘C’ tuned amplifier and derive its efficiency. (10)
(ii) Explain Hazeltine Neutralization Method. (6)
14. (a) (i) Sketch and define transistor switching times. (8)
(ii) What is a clipper? Explain the operation of positive and negative
diode clippers with waveforms. (8)
Or
(b) (i) Explain astable multivibrator with neat sketch of waveforms at
collector and base of transistors used in the circuit. (10)
(ii) Determine the value of capacitors to be used in an astable
multivibrator to provide a train of pulse s µ 2 wide at a repetition
rate of 100 KHz if = = k R R 20 2 1 . (6)
15. (a) (i) Explain about astable blocking oscillator with base timing. (10)
(ii) The diode controlled astable blocking oscillator has the parameters
10 = CC V V, V VB 5 . 0 = , 2 = n , = K R 5 . 1 , =10 f R , V Vr 9 = ,
mH L 3 = and pF C 100 = . Calculate the frequency of oscillation and
duty cycle. (6)
Or
(b) Write about Miller Integrator and Current-Time Base Circuit with
waveform. (16)

EC2205 ELECTRONIC CIRCUITS — I ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

 ELECTRONIC CIRCUITS — I ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

sub code: EC2205

ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER,  EC2205 ELECTRONIC CIRCUITS — I IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

B.E./B.Tech. DEGREE EXAMINATION, APRIL/MAY 2010

Third Semester

Electronics and Communication Engineering

EC2205 — ELECTRONIC CIRCUITS — I

(Regulation 2008)

Time: Three hours Maximum: 100 Marks

Answer ALL Questions

PART A — (10 × 2 = 20 Marks)

1. Define stability factor.
2. Calculate the value of feedback resistor (Rs) required to self bias an N-channel
JFET with IDSS = 40 mA, Vp = -10 v and VGSQ = -5V.
3. Define Miller's theorem.
4. What is the coupling schemes used in multistage amplifiers?
5. Give the expressions for gain bandwidth product for voltage and current.
6. What do you mean by amplifier rise time?
7. What is cross over distortion?
8. Draw the circuit of Class-D amplifier.
9. Compare the half-wave and full-wave rectifiers.
10. What are the advantages of SMPS?

PART B — (5 × 16 = 80 Marks)

11. (a) (i) Explain the fixed bias method and derive an expression for the
stability factor. (8)
(ii) Explain the voltage divider bias method and derive an expression
for the stability factor. (8)
Or
(b) (i) Explain the circuit which uses a diode to compensate for changes in
VBE and in ICO. (12)
(ii) Discuss the operation of thermistor compensation. (4)
12. (a) (i) Derive the expressions for the following of a small signal transistor
amplifier in terms of the h-parameters
(1) current gain
(2) voltage gain
(3) input impedance
(4) output admittance. (12)
(ii) Compare CB, CE and CC amplifiers. (4)
Or
(b) (i) Explain the operation of emitter coupled differential amplifier. (12)
(ii) Discuss the transfer characteristics of the differential amplifier. (4)
13. (a) Discuss the low frequency response and the high frequency response of
an amplifier. (16)
Or
(b) Explain the operation of high frequency common source FET amplifier
with neat diagram. Derive the expression for (i) voltage gain (ii) input
admittance (iii) input capacitance (iv) output admittance. (16)


14. (a) (i) Explain the operation of the transformer coupled class A audio
power amplifier. (12)
(ii) Explain the terms conversion efficiency and maximum value of
efficiency used in audio power amplifiers. (4)
Or
(b) Explain the operation of the class-B push pull power amplifier with neat
diagram and list its advantages. (16)
15. (a) Derive the expressions for the rectification efficiency, ripple factor,
transformer utilization factor, form factor and peak factor of
(i) half wave rectifier
(ii) full wave rectifier. (16)
Or
(b) Explain the operation of
(i) Voltage multiplier (8)
(ii) Switched mode power supply. (8)

EC2204 SIGNALS AND SYSTEMS ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

 SIGNALS AND SYSTEMS ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

SUB CODE :EC2204

ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER,  EC2204 SIGNALS AND SYSTEMS IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

B.E./B.Tech. DEGREE EXAMINATION, APRIL/MAY 2010

Third Semester

Electronics and Communication Engineering

EC2204 — SIGNALS AND SYSTEMS

(Regulation 2008)

Time: Three hours Maximum: 100 Marks

Answer ALL Questions

PART A — (10 × 2 = 20 Marks)

1. Define unit impulse and unit step signals.
2. When is a system said to be memoryless? Give an example.
3. State any two properties of Continuous – Time Fourier Transform.
4. Find the Laplace transform of the signal ) ( ) ( t u e t x at − = .
5. State the convolution integral for continuous time LTI systems.
6. What is the impulse response of two LTI systems connected in parallel?
7. State the Sampling theorem.
8. State the sufficient condition for the existence of DTFT for an aperiodic
sequence ) (n x .
9. Define one sided Z-transform and Two-sided Z-transform.
10. Define the shifting property of the discrete time unit Impulse function.

PART B — (5 × 16 = 80 Marks)

11. (a) Distinguish between the following:
(i) Continuous Time Signal and Discrete Time Signal. (4)
(ii) Unit step and Unit Ramp functions. (4)
(iii) Periodic and Aperiodic signals. (4)
(iv) Deterministic and Random signals. (4)
Or
(b) (i) Find whether the signal ) 1 4 ( sin ) 1 10 ( cos 2 ) ( − − + = t t t x is periodic
or not. (4)
(ii) Find the summation ∑∞
− =
−
8
2 ) 2 (
n
n n e δ . (4)
(iii) Explain the properties of unit impulse function. (4)
(iv) Find the fundamental period T of the continuous time signal




+ =
6
10 cos 20 ) (
π
πt t x . (4)
12. (a) (i) Find the trigonometric Fourier series for the periodic signal ) (t x
shown in the figure given below : (10)
(ii) Explain the Fourier spectrum of a periodic signal ) (t x . (6)
Or
(b) (i) Find the Laplace transform of the signal
) ( ) ( ) ( t u e t u e t x bt t a − + = − − . (8)
(ii) Find the Fourier transform of
t e t x
− = ) ( for 1 1 ≤ ≤ − t
otherwise 0 = . (8)
 132  132  132 
E 3074 3
13. (a) (i) Explain the steps to compute the convolution integral. (8)
(ii) Find the convolution of the following signals: (8)
) ( ) ( 2 t u e t x t − =
) 2 ( ) ( + = t u t h .
Or
(b) (i) Using Laplace transform, find the impulse response of an LTI
system described by the differential equation
) ( ) ( 2
) ( ) (
2
2
t x t y
dt
t dy
t d
t y d = − − . (8)
(ii) Explain the properties of convolution integral. (8)
14. (a) (i) Find the Fourier Transform of
N n
N n A n x
> =
≤ =
0
) (
. (8)
(ii) Explain any four properties of DTFT. (8)
Or
(b) (i) Find the Z-transform of the given signal ) (n x and find ROC.
( ) ( ) sin ( ) o
x n w n u n =     . (10)
(ii) Describe the sampling operation and explain how aliasing error can
be prevented. (6)
15. (a) (i) Find the impulse response of the discrete time system described by
the difference equation
) 1 ( ) ( 2 ) 1 ( 3 ) 2 ( − = + − − − n x n y n y n y . (8)
(ii) Discuss the block diagram representation for LTI discrete time
systems. (8)
Or
(b) (i) Describe the state variable model for discrete time systems. (8)
(ii) Find the state variable matrices A, B, C, D for the equation
) 2 ( 6 ) 1 ( 5 ) ( ) 2 ( 2 ) 1 ( 3 ) ( − + − + = − − − − n x n x n x n y n y n y . (8)

EC2203 DIGITAL ELECTRONICS ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

DIGITAL ELECTRONICS ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

SUBJECT CODE: EC 2203 

ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER,  EC2203 DIGITAL ELECTRONICS IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

B.E./B.Tech. DEGREE EXAMINATION, APRIL/MAY 2010

Third Semester

Electronics and Communications Engineering

EC2203 — DIGITAL ELECTRONICS

(Regulation 2008)

Time: Three hours Maximum: 100 Marks

Answer ALL Questions

PART A — (10 × 2 = 20 Marks)

1. State DeMorgan’s theorem.
2. Draw an active-high tri-state buffer and write its truth table.
3. Write an expression for borrow and difference in a full subtractor circuit.
4. Draw the circuits diagram for 4 bit Odd parity generator.
5. Mention any two differences between the edge triggering and level triggering.
6. What is meant by programmable counter? Mention its application.
7. What is meant by memory expansion? Mention its limit.
8. What are the advantages of static RAM compared to Dynamic RAM?
9. Draw the block diagram for Moore model.
10. What are hazard free digital circuits?

PART B — (5 × 16 = 80 Marks)

11. (a) (i) Express the Boolean function as
(1) POS form
(2) SOP form
D = (A’ + B) (B’ + C) (4)
(ii) Minimize the given terms
πM (0, 1, 4, 11, 13, 15) + πd (5, 7, 8) using Quine-McClusky
methods and verify the results using K-map methods. (12)
Or
(b) (i) Implement the following function using NOR gates. (8)
Output = 1 when the inputs are ) 4 , 3 , 2 , 1 , 0 ( m ∑
= 0 when the inputs are ) 7 , 6 , 5 ( m ∑ .
(ii) Discuss the general characteristic of TTL and CMOS logic families.
(8)
12. (a) (i) Derive the equation for a 4-bit look ahead carry adder circuit. (6)
(ii) Draw and explain the block diagram of a 4-bit serial adder to add
the contents of two registers. (10)
Or
(b) (i) Multiply (1011)2 by (1101)2 using addition and shifting operation
also draw block diagram of the 4-bit by 4 bit parallel multiplier. (8)
(ii) Design and implement the conversion circuits for Binary code to
gray code. (8)
13. (a) (i) Construct a clocked JK flip flop which is triggered at the positive
edge of the clock pulse from a clocked SR flip flop consisting of
NOR gates. (4)
(ii) Design a synchronous up/down counter that will count up from zero
to one to two to three, and will repeat whenever an external input x
is logic 0, and will count down from three to two to one to zero, and
will repeat whenever the external input x is logic 1. Implement your
circuit with one TTL SN74LS76 device and one TTL SN74LS00
device. (12)
Or
(b) (i) Write down the Characteristic table for the JK flip flop with
NOR gates. (4)
(ii) What is meant by Universal Shift Register? Explain the principle of
Operation of 4-bit Universal Shift Register. (12)
14. (a) (i) We can expand the word size of a RAM by combining two or more
RAM chips. For instance, we can use two 32 × 8 memory chips
where the number 32 represents the number of words and 8
represents the number of bits per word, to obtain a 32 × 16 RAM. In
this case the number of words remains the same but the length of
each word will two bytes long. Draw a block diagram to show how
we can use two 16 × 4 memory chips to obtain a 16 × 8 RAM. (8)
(ii) Explain the principle of operation of Bipolar SRAM cell. (8)
Or
(b) (i) A combinational circuit is defined as the functions
F1 = AB’C’+AB’C+ABC
F2 = A’BC+AB’C+ABC
Implement the digital circuit with a PLA having 3 inputs, 3 product
terms, and 2 outputs. (8)
(ii) Write a note on SRAM based FPGA. (8)
15. (a) For the circuit shown in figure, write down the state table and draw the
state diagram and analyze the operation. (16)
Or
(b) What are called as essential hazards? How does the hazard occur in
sequential circuits? How can the same be eliminated using SR latches?
Give an example. (16)

EC2202 DATA STRUCTURES AND OBJECT ORIENTED PROGRAMMING IN C++ ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

DATA STRUCTURES AND OBJECT ORIENTED PROGRAMMING IN C++   ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT 

SUB CODE: EC 2202 

  ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER EC2202 DATA STRUCTURES AND OBJECT ORIENTED PROGRAMMING IN C++ , IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

B.E./B.Tech. DEGREE EXAMINATION, APRIL/MAY 2010

Third Semester

Electronics and Communication Engineering

EC2202 — DATA STRUCTURES AND OBJECT ORIENTED

PROGRAMMING IN C ++

(Regulation 2008)

Time: Three hours Maximum: 100 Marks

Answer ALL Questions

PART A — (10 × 2 = 20 Marks)

1. How is a class declared in C++?
2. What is a scope resolution operator and how can it be used for global variable?
3. What is meant by binding?
4. How the pointer is implemented in C++?
5. Write any two data structures used in Operating System?
6. What are the representations of Big and small ‘O’ notations?
7. How many trees are possible with 3 nodes?
8. What is a spanning tree?
9. What is the feature of bucket sort algorithm?
10. Define dynamic programming.

PART B — (5 × 16 = 80 Marks)

11. (a) (i) Give the syntax and usage of the reserved word inline with two
examples. (8)
(ii) Explain the importance of constructors and destructors with
example. (8)
Or
(b) What is operator overloading? Overload the numerical operators ‘+’and ‘/’
for complex numbers “addition” and “division” respectively. (16)
12. (a) (i) Define friend class and specify its importance. Explain with
suitable example. (8)
(ii) Discuss Virtual function and polymorphism with example. (8)
Or
(b) (i) Explain the concept of inheritance by considering an example of
“vehicle”. (8)
(ii) Explain the operators used for dynamic memory allocation with
examples. (8)
13. (a) (i) Explain Priority Queues and how are binary heaps used in that. (8)
(ii) Explain the properties of heap. (8)
Or
(b) (i) Write a C ++ program to implement Stack and its operations PUSH
and POP. (10)
(ii) What is hashing? Classify hashing functions based on the various
methods. (6)
14. (a) (i) Traverse the tree given below using Inorder, Preorder and
Postorder traversals. (10)
(ii) Convert the expression ((A + B) * C - (D - E) ^ (F + G)) to equivalent
Prefix and postfix notations. (6)
Or

(b) (i) Convert the given graph with weighted edges to minimal spanning
tree. (10)
(ii) Write a short note on AVL trees. (6)
15. (a) Explain the algorithm of Quicksort by sorting the following set of
numbers as an example:
42 47 52 57 62 37 32 27 22
Or
(b) Describe divide and conquer technique with the help of mergesort. (16)

EC2201 ELECTRICAL ENGINEERING ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

 ELECTRICAL ENGINEERING ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER, IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER,  EC2201 ELECTRICAL ENGINEERING IMPORTANT QUESTIONS, 2 MARKS AND 16 MARKS QUESTIONS FOR ECE DEPARTMENT

B.E./B.Tech. DEGREE EXAMINATION, APRIL/MAY 2010

Third Semester

Electronics and Communication Engineering

EC2201 — ELECTRICAL ENGINEERING

(Regulation 2008)

Time: Three hours Maximum: 100 Marks

Answer ALL Questions

PART A — (10 × 2 = 20 Marks)

1. What are the conditions to be fulfilled for the self-excitation of a dc shunt
generator?
2. What are the functionS of interpoles and how are the interpoles windings
connected?
3. The emf per turn of a single phase, 6.6 kV/440 V, 50 Hz Transformer is
approximately 12 V.
Calculate
(a) the number of turns in the HV and LV windings and
(b) the net cross-sectional area of the core for a maximum flux density of
1.5 T.
4. Define voltage regulation of a transformer.
5. Why cannot an induction motor run at synchronous speed?
6. Why are single phase induction motors not self-starting?
7. What are the causes of faulty starting of a synchronous motor?
8. What are the applications of stepper motors?
9. Why are insulators used with overhead lines?
10. Define skin effect.

PART B — (5 × 16 = 80 Marks)

11. (a) (i) Describe with a neat sketch, the construction of a d.c. machine.
(ii) A separately excited dc generator running at 1000 r.p.m. supplied
110 A at 220 V to a resistive load. If the load resistance remains
constant, what will the load current if the speed is reduced to
800 r.p.m? Armature resistance is 0.02 . Field current is
unaltered. Assume a voltage drop of 1 V per brush. Ignore the effect
of armature reaction.
Or
(b) (i) Derive from the first principle, an expression for the torque
developed in d.c. motor.
(ii) In a brake test on a dc shunt motor, the load on one side of the
brake was 35 kg and on the other side 5 kg. The motor was running
at 1500 r.p.m. its input being 34 A at 400 V. The diameter of the
pulley is 50 c.m. Determine the torque and efficiency of the motor.
12. (a) (i) From first principles, derive the emf equation of a transformer. Also
show that the voltage induced per turn is the same, whether it is
primary or secondary.
(ii) A single phase transformer with a ratio of 6.6. kV/415 V takes a
no-load current of 0.75 A at 0.22 p.f. If the secondary supplies a
current of 120 A at 0.8 p.f. calculate the total current taken by the
primary.
Or
(b) (i) Develop an equivalent circuit for a single phase two winding
transformer.
(ii) Calculate the full-load efficiency at 0.8 p.f. and the voltage at the
secondary terminals when supplying full load secondary current at
unity power factor, for a 4 kVA, 200/400 V, 50 Hz, single phase
transformer of which the following are the test results :
OC test (on primary) : V = 200 V ; I = 0.8 A ; W = 50 W
SC test (on secondary) : V = 17.5 V ; I = 9 A; W = 50 W
13. (a) (i) Explain with neat sketches, the principle of operation of a threephase
induction motor.
(ii) A 6 pole, 3 phase, 50 Hz induction motor develops a maximum
torque of 30 Nm at 960 r.p.m. Determine the torque exerted by the
motor at 5% slip. The rotor resistance per phase is 0.6 .
Or
(b) Discuss briefly the various methods of speed control of three-phase
induction motors.

14. (a) (i) Derive the emf equation of an alternator. Discuss the effect of
winding factor on the induced emf.
(ii) Explain the speed-torque characteristics of a reluctance motor.
Or
(b) (i) A 500 kVA, 3.3. kV, 3-phase, star-connected alternator is found to
give a short circuit current of 290 A at normal field current. Its
effective winding resistance per phase is 0.7 . Estimate the full
load of voltage regulation by EMF method for 0.8 pf lagging.
(ii) Explain the speed-torque characteristics of a hysteresis motor.
15. (a) (i) Draw the single diagram of a typical a.c. power supply scheme.
(ii) With a neat sketch, explain the intersheath grading of cables.
Or
(b) (i) Explain briefly the advantages of EHVAC transmission over
EHVDC transmission.
(ii) Draw the layout of a substation with the main equipments.